1. Field of the Invention
The present invention relates to a tooth filling or tooth repairing process and an instrument for shaping and curing tool composite material in a temporary cavity that has been established by a matrix band placed around the occlusal part of a molar or premolar to be filled or repaired.
2. Description of the Related Art
The occlusal surface of a premolar or molar is normally repaired by applying a thin flexible, normally metallic, matrix band around the tooth with the aid of a matrix holder, so that the band will project beyond the surface of the tooth and a filling of composite material is built-up in one or more layers (increments) in the cavity defined by the matrix band and the tooth, said layer or layers each having a thickness of 2-3 mm. The layer or layers is/are light-hardened. The soft, or non-hardened, composite filling can be pressed down in the cavity with the aid of a narrow, generally pin-like tool which is ball-shaped at its tip and carried on one end of an instrument handle, so that the tool, whose cross-sectional area is much smaller than the area of the occlusal surface, can be pushed down into the composite and used to press the composite out to the peripheral walls of the cavity. The instrument is translucent to light that will harden the composite material, so as to enable the composite to be hardened at the pointed part of the tool.
The ball-shaped tip of the tool can be used to form grooves in the composite material on the occlusal surface prior to hardening said composite material, with the purpose of recreating a topography similar to the topography of a normal occlusal surface of a molar or premolar.
One problem with this known technique is that it is difficult to shape the composite material on the occlusal surface to a correct topography with the aid of the tool of said instrument. Another problem resides in the difficulty in establishing good contact between the filled tooth and its neighboring teeth. Furthermore, the work involved in shaping a correct occlusal surface is relatively laborious.